Compositions and methods for inhibiting plant pathogens

Abstract

The present specification provides, in one aspect, a method of treating or inhibiting infection of a plant by a plant pathogen. The method includes contacting the plant with an amount of a cranberry composition effective to inhibit the plant pathogen. In another aspect, the present specification provides a composition for treatment of a plant disease. The composition includes a cranberry composition and a carrier that delivers the cranberry composition to at least a portion of a phloem of a citrus plant.

What is claimed is: 
     
       1. A method of treating or inhibiting infection of a citrus plant by a bacterial plant pathogen, the method comprising:
 providing a composition comprising phenolics at 3 mg/g to 100 mg/g, a cranberry solids content of about 1 to about 30 Brix, and quinic acid at 0.01% to 14%, wherein the composition is dissolvable in water; wherein the phenolics comprise:
 anthocyanin at up to 100,000 mg/kg of the composition, and 
 proanthocyanidin at 2,500 mg/kg of the composition to 100,000 mg/kg of the composition; and 
 
 contacting a citrus plant infected with a bacterial plant pathogen with an amount of the composition effective to inhibit the bacterial plant pathogen. 
 
     
     
       2. The method of  claim 1 , wherein contacting the citrus plant comprises brushing or spraying onto the citrus plant, or injecting into the citrus plant, the composition. 
     
     
       3. The method of  claim 1 , wherein contacting the citrus plant comprises spraying, drenching, mixing, or injecting the composition into soil surrounding the citrus plant. 
     
     
       4. The method of  claim 1 , wherein the composition further comprises a carrier that enables delivery of the composition to a phloem of the citrus plant. 
     
     
       5. The method of  claim 1 , wherein the composition further comprises a starch degrading enzyme. 
     
     
       6. The method of  claim 1 , wherein the composition further comprises a tannase enzyme. 
     
     
       7. The method of  claim 1 , wherein the phenolics comprise anthocyanins at about 1 mg/kg of the composition to about 5000 mg/kg of the composition. 
     
     
       8. The method of  claim 1 , wherein the phenolics comprise the proanthocyanidins at about 25,000 mg/kg of the composition to about 75,000 mg/kg of the composition. 
     
     
       9. The method according to  claim 1 , wherein the bacterial plant pathogen is α-proteobacterium  Candidatus Liberibacter asiaticus.    
     
     
       10. The method of  claim 1 , wherein the composition further comprises an adjuvant. 
     
     
       11. The method of  claim 10 , wherein the adjuvant is a surfactant. 
     
     
       12. The method of  claim 10 , wherein contacting the citrus plant having the bacterial plant pathogen infection with the amount of the composition effective to inhibit the bacterial plant pathogen comprises:
 delivering the composition to a phloem of the citrus plant. 
 
     
     
       13. The method of  claim 1 , wherein the composition further comprises malic acid, or citric acid, or both. 
     
     
       14. The method of  claim 1 , wherein the composition is a cranberry composition. 
     
     
       15. The method of  claim 14 , wherein the cranberry composition is a cranberry extract. 
     
     
       16. A method of treating or inhibiting infection of a citrus plant by a bacterial plant pathogen, the method comprising:
 providing a composition comprising phenolics at 3 mg/g to 100 mg/g, a cranberry solids content of about 1 to about 30 Brix, and at least one of quinic acid, malic acid, and citric acid, wherein the phenolics comprise benzoic acid at up to about 30 mg/g of the composition, wherein the composition is dissolvable in water; and 
 contacting a citrus plant infected with a bacterial plant pathogen with an amount of the composition effective to inhibit the bacterial plant pathogen. 
 
     
     
       17. The method according to  claim 16 , wherein the composition comprises quinic acid at about 0.01% to about 14%. 
     
     
       18. The method of  claim 16 , wherein the composition is a cranberry composition. 
     
     
       19. The method of  claim 18 , wherein the cranberry composition is a cranberry extract. 
     
     
       20. The method according to  claim 16 , wherein the bacterial plant pathogen is α-proteobacterium  Candidatus Liberibacter asiaticus.    
     
     
       21. The method of  claim 16 , wherein the composition further comprises an adjuvant. 
     
     
       22. The method of  claim 21 , wherein the adjuvant is a surfactant. 
     
     
       23. The method of  claim 21 , wherein contacting the citrus plant having the bacterial plant pathogen infection with the amount of the composition effective to inhibit the bacterial plant pathogen comprises:
 delivering the composition to a phloem of the citrus plant. 
 
     
     
       24. The method of  claim 16 , wherein contacting the citrus plant comprises brushing or spraying onto the plant, or injecting into the plant, the composition. 
     
     
       25. The method of  claim 16 , wherein contacting the citrus plant comprises spraying, drenching, mixing, or injecting the composition into soil surrounding the plant. 
     
     
       26. The method of  claim 16 , wherein the composition further comprises a carrier that enables delivery of the composition to a phloem of the citrus plant. 
     
     
       27. The method of  claim 16 , wherein the composition further comprises a starch degrading enzyme. 
     
     
       28. The method of  claim 16 , wherein the composition comprises the benzoic acid at up to about 1 mg/g. 
     
     
       29. The method of  claim 16 , wherein the composition comprises the benzoic acid at up to about 5 mg/g. 
     
     
       30. The method of  claim 16 , wherein the composition comprises the benzoic acid at up to about 10 mg/g. 
     
     
       31. The method of  claim 16 , wherein the phenolics comprise:
 proanthocyanidin at 2,500 mg/kg of the composition to 100,000 mg/kg of the composition. 
 
     
     
       32. A method of treating or inhibiting infection of a citrus plant by a bacterial plant pathogen, the method comprising:
 providing a composition comprising phenolics at 3 mg/g to 100 mg/g, wherein the phenolics comprise benzoic acid at up to about 30 mg/g of the composition, wherein the composition is dissolvable in water, wherein the composition comprises a cranberry solids content of about 1 to about 30 Brix; and 
 contacting a citrus plant infected with a bacterial plant pathogen with an amount of the composition effective to inhibit the bacterial plant pathogen. 
 
     
     
       33. The method according to  claim 32 , wherein the bacterial plant pathogen is α-proteobacterium  Candidatus Liberibacter asiaticus.    
     
     
       34. The method according to  claim 32 , wherein the composition further comprises a carrier that enables delivery of the composition to a phloem of the citrus plant. 
     
     
       35. The method according to  claim 32 , wherein the composition further comprises an adjuvant. 
     
     
       36. The method of  claim 32 , wherein the phenolics comprise proanthocyanidin at about 2,000 mg/kg to about 2,500 mg/kg. 
     
     
       37. The method of  claim 32 , wherein the phenolics comprise anthocyanins up to about 100,000 mg/kg. 
     
     
       38. The method of  claim 32 , wherein contacting the citrus plant having the bacterial plant pathogen infection with the amount of the composition effective to inhibit the bacterial plant pathogen comprises:
 delivering the composition to a phloem of the citrus plant, a xylem of the citrus plant, or both.